I recently characterized walking as 'pedestrian'. Truly, walking and running are different species. You incur 3-10 times your body weight in impact force when you run. The energy systems you use when you walk versus when you run are generally different.
But, there are different species of running as well. There is running and then there is 'running fast'. Many individual clients engage me because they want to 'get faster'. Most of the time they aren't getting faster for the simple fact that they aren't 'running faster'.
Chances are, they've been doing the same thing over and over again which is often just going out and logging the miles. There's nothing wrong with this. But, just as walking is markedly different (and yet very similar) to running, running FAST is markedly different from simply 'running'.
Fundamentally, running fast simply HURTS. I came face to face with this uncomfortable fact during my first cross country race. I had spent several weeks prior to the race attempting to become a runner by going out with the cross country team and simply hanging on for dear life while we logged anywhere from 3-6 miles.
Our first race arrived and I had no idea what kind of pain was waiting for me. I went out hard, but nowhere near the front of the pack. Within the first mile or so of the race I was wondering if I was about to pass out or throw up....perhaps both in no particular order.
Speed hurts because you're taxing all the systems you use logging miles at a comfortable, conversational pace at a much higher level. You're leveraging more muscle groups and a greater range of motion. Your lungs labor to supply the oxygen you need to keep moving.
It took one race for me to become acquainted with the beast known as 'running fast'. I have yet to tame this beast. But, I have learned how to work with it, direct it, embrace it, and use it to my advantage on occasion.
Speed feels dangerous and it is. Speed begets speed. Speed kills. It can kill you or kill those trying to pass you. In an ideal world, you're looking at the latter. Once I realized the utility and thrill of running fast, I got over the pain and embraced hauling ass.
To clarify, I'm not the kind of guy who generally throws caution to the wind. I don't log any miles on a bike because the possibility of wiping out at 30+ miles per hour is too frightening of a prospect for me. Redlining behind the wheel of a car, motorcycle, plane, or even a bike poses the risk of serious injury or death.
If I redline while out on the road and take a tumble, I'll get a bit nicked up, but it's likely I'll simply get back up a bit bloodied and keep going.
So, I'm cool with risk....to a point. I run because there is nothing quite like listening to 'Welcome to the Jungle' and redlining a few miles out on the road. I run because I feel the need for speed.